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Sujkowski A, Ranxhi B, Bangash ZR, Chbihi ZM, Prifti MV, Qadri Z, Alam N, Todi SV, Tsou WL. Progressive degeneration in a new Drosophila model of spinocerebellar ataxia type 7. Sci Rep 2024; 14:14332. [PMID: 38906973 PMCID: PMC11192756 DOI: 10.1038/s41598-024-65172-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 06/18/2024] [Indexed: 06/23/2024] Open
Abstract
Spinocerebellar ataxia type 7 (SCA7) is a progressive neurodegenerative disorder resulting from abnormal expansion of an uninterrupted polyglutamine (polyQ) repeat in its disease protein, ataxin-7 (ATXN7). ATXN7 is part of Spt-Ada-Gcn5 acetyltransferase (SAGA), an evolutionarily conserved transcriptional coactivation complex with critical roles in chromatin remodeling, cell signaling, neurodifferentiation, mitochondrial health and autophagy. SCA7 is dominantly inherited and characterized by genetic anticipation and high repeat-length instability. Patients with SCA7 experience progressive ataxia, atrophy, spasticity, and blindness. There is currently no cure for SCA7, and therapies are aimed at alleviating symptoms to increase quality of life. Here, we report novel Drosophila lines of SCA7 with polyQ repeats in wild-type and human disease patient range. We find that ATXN7 expression has age- and polyQ repeat length-dependent reduction in fruit fly survival and retinal instability, concomitant with increased ATXN7 protein aggregation. These new lines will provide important insight on disease progression that can be used in the future to identify therapeutic targets for SCA7 patients.
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Affiliation(s)
- Alyson Sujkowski
- Department of Pharmacology, Wayne State University School of Medicine, 540 E Canfield, Scott Hall Rm 3108, Detroit, MI, 48201, USA
| | - Bedri Ranxhi
- Department of Pharmacology, Wayne State University School of Medicine, 540 E Canfield, Scott Hall Rm 3108, Detroit, MI, 48201, USA
| | - Zoya R Bangash
- Department of Pharmacology, Wayne State University School of Medicine, 540 E Canfield, Scott Hall Rm 3108, Detroit, MI, 48201, USA
| | - Zachary M Chbihi
- Department of Pharmacology, Wayne State University School of Medicine, 540 E Canfield, Scott Hall Rm 3108, Detroit, MI, 48201, USA
| | - Matthew V Prifti
- Department of Pharmacology, Wayne State University School of Medicine, 540 E Canfield, Scott Hall Rm 3108, Detroit, MI, 48201, USA
| | - Zaina Qadri
- Department of Pharmacology, Wayne State University School of Medicine, 540 E Canfield, Scott Hall Rm 3108, Detroit, MI, 48201, USA
| | - Nadir Alam
- Department of Pharmacology, Wayne State University School of Medicine, 540 E Canfield, Scott Hall Rm 3108, Detroit, MI, 48201, USA
| | - Sokol V Todi
- Department of Pharmacology, Wayne State University School of Medicine, 540 E Canfield, Scott Hall Rm 3108, Detroit, MI, 48201, USA
- Department of Neurology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Wei-Ling Tsou
- Department of Pharmacology, Wayne State University School of Medicine, 540 E Canfield, Scott Hall Rm 3108, Detroit, MI, 48201, USA.
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2
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Canic T, Lopez J, Ortiz-Vega N, Zhai RG, Syed S. High-resolution, high-throughput analysis of Drosophila geotactic behavior. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.07.597941. [PMID: 38895419 PMCID: PMC11185704 DOI: 10.1101/2024.06.07.597941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Drosophila innate response to gravity, geotaxis, has been previously used to assess the impact of aging and disease on motor performance. Despite its rich history, fly geotaxis continues to be largely measured manually and assessed through simplistic metrics. The manual nature of this assay introduces substantial experimental variability while simplistic metrics provide limited analytic insights into the behavior. To address these shortcomings, we have constructed a fully automated, programable apparatus, and developed a multi-object tracking software capable of following sub-second movements of individual flies, thus allowing reproducible, detailed, and quantitative analysis of geotactic behavior. The apparatus triggers and monitors geotaxis of 10 fly cohorts simultaneously, with each cohort consisting of up to 7 flies. The tracking program isolates cohorts and records individual fly coordinate outputs allowing for simultaneous multi-group, multi-fly tracks per experiment, greatly improving throughput and resolution. The algorithm tracks individual flies during the entire run with ~97% accuracy, yielding detailed climbing curve, speed, and movement direction with 1/30 second resolution. Our tracking also allows the construction of multi-variable metrics and the detection of transitory movement phenotypes, such as slips and falls, which have thus far been neglected in geotaxis studies due to limited spatio-temporal resolution. Through a combination of automation and robust tracking, the platform is therefore poised to advance Drosophila geotaxis assay into a comprehensive assessment of locomotor behavior.
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Affiliation(s)
- Tijana Canic
- Department of Physics, University of Miami, Coral Gables, FL, USA
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Juan Lopez
- Department of Physics, University of Miami, Coral Gables, FL, USA
| | - Natalie Ortiz-Vega
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - R. Grace Zhai
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, USA
- Department of Neurology, University of Chicago, Chicago, IL, USA
| | - Sheyum Syed
- Department of Physics, University of Miami, Coral Gables, FL, USA
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3
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Yip C, Wyler SC, Liang K, Yamazaki S, Cobb T, Safdar M, Metai A, Merchant W, Wessells R, Rothenfluh A, Lee S, Elmquist J, You YJ. Neuronal E93 is required for adaptation to adult metabolism and behavior. Mol Metab 2024; 84:101939. [PMID: 38621602 PMCID: PMC11053319 DOI: 10.1016/j.molmet.2024.101939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 04/07/2024] [Accepted: 04/09/2024] [Indexed: 04/17/2024] Open
Abstract
OBJECTIVE Metamorphosis is a transition from growth to reproduction, through which an animal adopts adult behavior and metabolism. Yet the neural mechanisms underlying the switch are unclear. Here we report that neuronal E93, a transcription factor essential for metamorphosis, regulates the adult metabolism, physiology, and behavior in Drosophila melanogaster. METHODS To find new neuronal regulators of metabolism, we performed a targeted RNAi-based screen of 70 Drosophila orthologs of the mammalian genes enriched in ventromedial hypothalamus (VMH). Once E93 was identified from the screen, we characterized changes in physiology and behavior when neuronal expression of E93 is knocked down. To identify the neurons where E93 acts, we performed an additional screen targeting subsets of neurons or endocrine cells. RESULTS E93 is required to control appetite, metabolism, exercise endurance, and circadian rhythms. The diverse phenotypes caused by pan-neuronal knockdown of E93, including obesity, exercise intolerance and circadian disruption, can all be phenocopied by knockdown of E93 specifically in either GABA or MIP neurons, suggesting these neurons are key sites of E93 action. Knockdown of the Ecdysone Receptor specifically in MIP neurons partially phenocopies the MIP neuron-specific knockdown of E93, suggesting the steroid signal coordinates adult metabolism via E93 and a neuropeptidergic signal. Finally, E93 expression in GABA and MIP neurons also serves as a key switch for the adaptation to adult behavior, as animals with reduced expression of E93 in the two subsets of neurons exhibit reduced reproductive activity. CONCLUSIONS Our study reveals that E93 is a new monogenic factor essential for metabolic, physiological, and behavioral adaptation from larval behavior to adult behavior.
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Affiliation(s)
- Cecilia Yip
- The Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Steven C Wyler
- The Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Katrina Liang
- The Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Shin Yamazaki
- Department of Neuroscience and Peter O'Donnell Jr. Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Tyler Cobb
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Maryam Safdar
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Aarav Metai
- The Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Warda Merchant
- The Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Robert Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Adrian Rothenfluh
- Huntsman Mental Health Institute, Department of Psychiatry, University of Utah, Salt Lake City, UT, USA; Molecular Medicine Program, University of Utah, Salt Lake City, UT, USA
| | - Syann Lee
- The Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Joel Elmquist
- The Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Young-Jai You
- The Center for Hypothalamic Research, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA.
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4
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Zappia MP, Damschroder D, Westacott A, Wessells RJ, Frolov MV. The RU486-dependent activation of the GeneSwitch system in adult muscles leads to severe adverse effects in Drosophila. G3 (BETHESDA, MD.) 2024; 14:jkae039. [PMID: 38409337 PMCID: PMC11075533 DOI: 10.1093/g3journal/jkae039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/15/2024] [Accepted: 02/20/2024] [Indexed: 02/28/2024]
Abstract
Robust genetic systems to control the expression of transgenes in a spatial and temporal manner are a valuable asset for researchers. The GeneSwitch system induced by the drug RU486 has gained widespread use in the Drosophila community. However, some concerns were raised as negative effects were seen depending on the stock, transgene, stage, and tissue under study. Here, we characterized the adverse effects triggered by activating the GeneSwitch system in adult muscles using the MHC-GS-GAL4 driver. When a control, mock UAS-RNAi transgene was induced by feeding adult flies with RU486, we found that the overall muscle structure, including myofibrils and mitochondrial shape, was significantly disrupted and led to a significant reduction in the lifespan. Remarkably, lifespan was even shorter when 2 copies of the driver were used even without the mock UAS-RNAi transgene. Thus, researchers should be cautious when interpreting the results given the adverse effects we found when inducing RU486-dependent MHC-GS-GAL4 in adult muscles. To account for the impact of these effects we recommend adjusting the dose of RU486, setting up additional control groups, such as a mock UAS-RNAi transgene, as comparing the phenotypes between RU486-treated and untreated animals could be insufficient.
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Affiliation(s)
- Maria Paula Zappia
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Deena Damschroder
- Department of Physiology, Wayne State School of Medicine, Detroit, MI 48201, USA
| | - Anton Westacott
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Robert J Wessells
- Department of Physiology, Wayne State School of Medicine, Detroit, MI 48201, USA
| | - Maxim V Frolov
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607, USA
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5
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Richardson K, Sengupta M, Sujkowski A, Libohova K, Harris AC, Wessells R, Merry DE, Todi SV. A phenotypically robust model of spinal and bulbar muscular atrophy in Drosophila. J Neurosci Res 2024; 102:e25278. [PMID: 38284836 PMCID: PMC11237963 DOI: 10.1002/jnr.25278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 10/14/2023] [Accepted: 11/05/2023] [Indexed: 01/30/2024]
Abstract
Spinal and bulbar muscular atrophy (SBMA) is an X-linked disorder that affects males who inherit the androgen receptor (AR) gene with an abnormal CAG triplet repeat expansion. The resulting protein contains an elongated polyglutamine (polyQ) tract and causes motor neuron degeneration in an androgen-dependent manner. The precise molecular sequelae of SBMA are unclear. To assist with its investigation and the identification of therapeutic options, we report here a new model of SBMA in Drosophila melanogaster. We generated transgenic flies that express the full-length, human AR with a wild-type or pathogenic polyQ repeat. Each transgene is inserted into the same safe harbor site on the third chromosome of the fly as a single copy and in the same orientation. Expression of pathogenic AR, but not of its wild-type variant, in neurons or muscles leads to consistent, progressive defects in longevity and motility that are concomitant with polyQ-expanded AR protein aggregation and reduced complexity in neuromuscular junctions. Additional assays show adult fly eye abnormalities associated with the pathogenic AR species. The detrimental effects of pathogenic AR are accentuated by feeding flies the androgen, dihydrotestosterone. This new, robust SBMA model can be a valuable tool toward future investigations of this incurable disease.
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Affiliation(s)
- Kristin Richardson
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Medha Sengupta
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University Sidney Kimmel Medical College, Philadelphia, Pennsylvania, USA
| | - Alyson Sujkowski
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Kozeta Libohova
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Autumn C Harris
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan, USA
- Maximizing Access to Science Careers Program, Wayne State University, Detroit, Michigan, USA
| | - Robert Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Diane E Merry
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University Sidney Kimmel Medical College, Philadelphia, Pennsylvania, USA
| | - Sokol V Todi
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan, USA
- Maximizing Access to Science Careers Program, Wayne State University, Detroit, Michigan, USA
- Department of Neurology, Wayne State University School of Medicine, Detroit, Michigan, USA
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6
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Sujkowski AL, Ranxhi B, Prifti MV, Alam N, Todi SV, Tsou WL. Progressive degeneration in a new Drosophila model of Spinocerebellar Ataxia type 7. RESEARCH SQUARE 2023:rs.3.rs-3592641. [PMID: 38045332 PMCID: PMC10690306 DOI: 10.21203/rs.3.rs-3592641/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Spinocerebellar ataxia type 7 (SCA7) is a progressive neurodegenerative disorder resulting from abnormal expansion of polyglutamine (polyQ) in its disease protein, ataxin-7 (ATXN7). ATXN7 is part of Spt-Ada-Gcn5 acetyltransferase (SAGA), an evolutionarily conserved transcriptional coactivation complex with critical roles in chromatin remodeling, cell signaling, neurodifferentiation, mitochondrial health and autophagy. SCA7 is dominantly inherited and characterized by genetic anticipation and high repeat-length instability. Patients with SCA7 experience progressive ataxia, atrophy, spasticity, and blindness. There is currently no cure for SCA7, and therapies are aimed at alleviating symptoms to increase quality of life. Here, we report novel Drosophila lines of SCA7 with polyQ repeats in wild-type and human disease patient range. We find that ATXN7 expression has age- and polyQ repeat length-dependent reduction in survival and retinal instability, concomitant with increased ATXN7 protein aggregation. These new lines will provide important insight on disease progression that can be used in the future to identify therapeutic targets for SCA7 patients.
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Affiliation(s)
| | - Bedri Ranxhi
- Department of Pharmacology, Wayne State University School of Medicine
| | - Matthew V Prifti
- Department of Pharmacology, Wayne State University School of Medicine
| | - Nadir Alam
- Department of Pharmacology, Wayne State University School of Medicine
| | - Sokol V Todi
- Department of Pharmacology, Wayne State University School of Medicine
- Department of Neurology, Wayne State University School of Medicine
| | - Wei-Ling Tsou
- Department of Pharmacology, Wayne State University School of Medicine
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7
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Sujkowski AL, Ranxhi B, Prifti MV, Alam N, Todi SV, Tsou WL. Progressive degeneration in a new Drosophila model of Spinocerebellar Ataxia type 7. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.07.566106. [PMID: 37986914 PMCID: PMC10659390 DOI: 10.1101/2023.11.07.566106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Spinocerebellar ataxia type 7 (SCA7) is a progressive neurodegenerative disorder resulting from abnormal expansion of polyglutamine (polyQ) in its disease protein, ataxin-7 (ATXN7). ATXN7 is part of Spt-Ada-Gcn5 acetyltransferase (SAGA), an evolutionarily conserved transcriptional coactivation complex with critical roles in chromatin remodeling, cell signaling, neurodifferentiation, mitochondrial health and autophagy. SCA7 is dominantly inherited and characterized by genetic anticipation and high repeat-length instability. Patients with SCA7 experience progressive ataxia, atrophy, spasticity, and blindness. There is currently no cure for SCA7, and therapies are aimed at alleviating symptoms to increase quality of life. Here, we report novel Drosophila lines of SCA7 with polyQ repeats in wild-type and human disease patient range. We find that ATXN7 expression has age- and polyQ repeat length-dependent reduction in survival and retinal instability, concomitant with increased ATXN7 protein aggregation. These new lines will provide important insight on disease progression that can be used in the future to identify therapeutic targets for SCA7 patients.
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8
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Safdar M, Wessells RJ. Octopamine Rescues Endurance and Climbing Speed in Drosophila Clkout Mutants with Circadian Rhythm Disruption. Cells 2023; 12:2515. [PMID: 37947593 PMCID: PMC10648926 DOI: 10.3390/cells12212515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/18/2023] [Accepted: 10/23/2023] [Indexed: 11/12/2023] Open
Abstract
Circadian rhythm disturbances are associated with various negative health outcomes, including an increasing incidence of chronic diseases with high societal costs. While exercise can protect against the negative effects of rhythm disruption, it is not available to all those impacted by sleep disruptions, in part because sleep disruption itself reduces exercise capacity. Thus, there is a need for therapeutics that bring the benefits of exercise to this population. Here, we investigate the relationship between exercise and circadian disturbances using a well-established Drosophila model of circadian rhythm loss, the Clkout mutant. We find that Clkout causes reduced exercise capacity, measured as post-training endurance, flight performance, and climbing speed, and these phenotypes are not rescued by chronic exercise training. However, exogenous administration of a molecule known to mediate the effects of chronic exercise, octopamine (OA), was able to effectively rescue mutant exercise performance, including the upregulation of other known exercise-mediating transcripts, without restoring the circadian rhythms of mutants. This work points the way toward the discovery of novel therapeutics that can restore exercise capacity in patients with rhythm disruption.
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Affiliation(s)
| | - Robert J. Wessells
- Department of Physiology, School of Medicine, Wayne State University, Detroit, MI 48201, USA;
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9
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Richardson K, Wessells R. A novel panel of Drosophila TAFAZZIN mutants in distinct genetic backgrounds as a resource for therapeutic testing. PLoS One 2023; 18:e0286380. [PMID: 37756350 PMCID: PMC10529581 DOI: 10.1371/journal.pone.0286380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Accepted: 05/16/2023] [Indexed: 09/29/2023] Open
Abstract
Barth Syndrome is a rare, X-linked disorder caused by mutation of the gene TAFAZZIN (TAZ). The corresponding Tafazzin protein is involved in the remodeling of cardiolipin, a phospholipid with critical roles in mitochondrial function. While recent clinical trials have been promising, there is still no cure for Barth Syndrome. Because TAZ is highly conserved, multiple animal and cell culture models exist for pre-clinical testing of therapeutics. However, since the same mutation in different patients can lead to different symptoms and responses to treatment, isogenized experimental models can't fully account for human disease conditions. On the other hand, isogenized animal models allow for sufficient numbers to thoroughly establish efficacy for a given genetic background. Therefore, a combined method for testing treatments in a panel of isogenized cohorts that are genetically distinct from each other would be transformative for testing emerging pre-clinical therapies. To aid in this effort, we've created a novel panel of 10 Drosophila lines, each with the same TAZ mutation in highly diverse genetic backgrounds, to serve as a helpful resource to represent natural variation in background genetics in pre-clinical studies. As a proof of principle, we test our panel here using nicotinamide riboside (NR), a treatment with established therapeutic value, to evaluate how robust this therapy is across the 10 genetic backgrounds in this novel reference panel. We find substantial variation in the response to NR across backgrounds. We expect this resource will be valuable in pre-clinical testing of emerging therapies for Barth Syndrome.
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Affiliation(s)
- Kristin Richardson
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, United States of America
| | - Robert Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, United States of America
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10
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Cobb T, Hwang I, Soukar M, Namkoong S, Cho US, Safdar M, Kim M, Wessells RJ, Lee JH. Iditarod, a Drosophila homolog of the Irisin precursor FNDC5, is critical for exercise performance and cardiac autophagy. Proc Natl Acad Sci U S A 2023; 120:e2220556120. [PMID: 37722048 PMCID: PMC10523451 DOI: 10.1073/pnas.2220556120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 07/28/2023] [Indexed: 09/20/2023] Open
Abstract
Mammalian FNDC5 encodes a protein precursor of Irisin, which is important for exercise-dependent regulation of whole-body metabolism. In a genetic screen in Drosophila, we identified Iditarod (Idit), which shows substantial protein homology to mouse and human FNDC5, as a regulator of autophagy acting downstream of Atg1/Atg13. Physiologically, Idit-deficient flies showed reduced exercise performance and defective cold resistance, which were rescued by exogenous expression of Idit. Exercise training increased endurance in wild-type flies, but not in Idit-deficient flies. Conversely, Idit is induced upon exercise training, and transgenic expression of Idit in wild-type flies increased endurance to the level of exercise trained flies. Finally, Idit deficiency prevented both exercise-induced increase in cardiac Atg8 and exercise-induced cardiac stress resistance, suggesting that cardiac autophagy may be an additional mechanism by which Idit is involved in the adaptive response to exercise. Our work suggests an ancient role of an Iditarod/Irisin/FNDC5 family of proteins in autophagy, exercise physiology, and cold adaptation, conserved throughout metazoan species.
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Affiliation(s)
- Tyler Cobb
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201
| | - Irene Hwang
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109
| | - Michael Soukar
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109
| | - Sim Namkoong
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109
- Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, Gangwon 24341, Republic of Korea
| | - Uhn-Soo Cho
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109
| | - Maryam Safdar
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201
| | - Myungjin Kim
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109
| | - Robert J Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201
| | - Jun Hee Lee
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI 48109
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11
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Sujkowski A, Richardson K, Prifti MV, Wessells RJ, Todi SV. Endurance exercise ameliorates phenotypes in Drosophila models of spinocerebellar ataxias. eLife 2022; 11:e75389. [PMID: 35170431 PMCID: PMC8871352 DOI: 10.7554/elife.75389] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/15/2022] [Indexed: 11/24/2022] Open
Abstract
Endurance exercise is a potent intervention with widespread benefits proven to reduce disease incidence and impact across species. While endurance exercise supports neural plasticity, enhanced memory, and reduced neurodegeneration, less is known about the effect of chronic exercise on the progression of movement disorders such as ataxias. Here, we focused on three different types of ataxias, spinocerebellar ataxias type (SCAs) 2, 3, and 6, belonging to the polyglutamine (polyQ) family of neurodegenerative disorders. In Drosophila models of these SCAs, flies progressively lose motor function. In this study, we observe marked protection of speed and endurance in exercised SCA2 flies and modest protection in exercised SCA6 models, with no benefit to SCA3 flies. Causative protein levels are reduced in SCA2 flies after chronic exercise, but not in SCA3 models, linking protein levels to exercise-based benefits. Further mechanistic investigation indicates that the exercise-inducible protein, Sestrin (Sesn), suppresses mobility decline and improves early death in SCA2 flies, even without exercise, coincident with disease protein level reduction and increased autophagic flux. These improvements partially depend on previously established functions of Sesn that reduce oxidative damage and modulate mTOR activity. Our study suggests differential responses of polyQ SCAs to exercise, highlighting the potential for more extensive application of exercise-based therapies in the prevention of polyQ neurodegeneration. Defining the mechanisms by which endurance exercise suppresses polyQ SCAs will open the door for more effective treatment for these diseases.
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Affiliation(s)
- Alyson Sujkowski
- Department of Physiology, Wayne State University School of MedicineDetroitUnited States
- Department of Pharmacology, Wayne State University School of MedicineDetroitUnited States
| | - Kristin Richardson
- Department of Physiology, Wayne State University School of MedicineDetroitUnited States
| | - Matthew V Prifti
- Department of Pharmacology, Wayne State University School of MedicineDetroitUnited States
| | - Robert J Wessells
- Department of Physiology, Wayne State University School of MedicineDetroitUnited States
| | - Sokol V Todi
- Department of Pharmacology, Wayne State University School of MedicineDetroitUnited States
- Department of Neurology, Wayne State University School of MedicineDetroitUnited States
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12
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Ji J, Damschroder D, Bessert D, Lazcano P, Wessells R, Reynolds CA, Greenberg ML. NAD supplementation improves mitochondrial performance of cardiolipin mutants. Biochim Biophys Acta Mol Cell Biol Lipids 2022; 1867:159094. [PMID: 35051613 PMCID: PMC8883178 DOI: 10.1016/j.bbalip.2021.159094] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/28/2021] [Accepted: 12/09/2021] [Indexed: 12/01/2022]
Abstract
Cardiolipin (CL) deficiency causes mitochondrial dysfunction and aberrant metabolism that are associated in humans with the severe disease Barth syndrome (BTHS). Several metabolic abnormalities are observed in BTHS patients and model systems, including decreased oxidative phosphorylation, reduced tricarboxylic acid (TCA) cycle flux, and accumulated lactate and D-β-hydroxybutyrate, which strongly suggests that nicotinamide adenine dinucleotide (NAD) redox metabolism may be altered in CL-deficient cells. In this study, we identified abnormal NAD+ metabolism in multiple BTHS model systems and demonstrate that supplementation of NAD+ precursors such as nicotinamide mononucleotide (NMN) improves mitochondrial function. Improved mitochondrial function in the Drosophila model was associated with restored exercise endurance, which suggests a potential therapeutic benefit of NAD+ precursor supplementation in the management of BTHS patients.
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Affiliation(s)
- Jiajia Ji
- Department of Biological Sciences, College of Liberal Arts and Sciences, Wayne State University, Detroit, MI, United States of America
| | - Deena Damschroder
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, United States of America
| | - Denise Bessert
- Department of Emergency Medicine, Wayne State University School of Medicine, Detroit, MI, United States of America
| | - Pablo Lazcano
- Department of Biological Sciences, College of Liberal Arts and Sciences, Wayne State University, Detroit, MI, United States of America
| | - Robert Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, United States of America
| | - Christian A Reynolds
- Department of Emergency Medicine, Wayne State University School of Medicine, Detroit, MI, United States of America.
| | - Miriam L Greenberg
- Department of Biological Sciences, College of Liberal Arts and Sciences, Wayne State University, Detroit, MI, United States of America.
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13
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Sujkowski A, Wessells R. Exercise and Sestrin Mediate Speed and Lysosomal Activity in Drosophila by Partially Overlapping Mechanisms. Cells 2021; 10:cells10092479. [PMID: 34572128 PMCID: PMC8466685 DOI: 10.3390/cells10092479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/15/2021] [Accepted: 09/17/2021] [Indexed: 12/14/2022] Open
Abstract
Chronic exercise is widely recognized as an important contributor to healthspan in humans and in diverse animal models. Recently, we have demonstrated that Sestrins, a family of evolutionarily conserved exercise-inducible proteins, are critical mediators of exercise benefits in flies and mice. Knockout of Sestrins prevents exercise adaptations to endurance and flight in Drosophila, and similarly prevents benefits to endurance and metabolism in exercising mice. In contrast, overexpression of dSestrin in muscle mimics several of the molecular and physiological adaptations characteristic of endurance exercise. Here, we extend those observations to examine the impact of dSestrin on preserving speed and increasing lysosomal activity. We find that dSestrin is a critical factor driving exercise adaptations to climbing speed, but is not absolutely required for exercise to increase lysosomal activity in Drosophila. The role of Sestrin in increasing speed during chronic exercise requires both the TORC2/AKT axis and the PGC1α homolog spargel, while dSestrin requires interactions with TORC1 to cell-autonomously increase lysosomal activity. These results highlight the conserved role of Sestrins as key factors that drive diverse physiological adaptations conferred by chronic exercise.
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14
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Cobb T, Damschroder D, Wessells R. Sestrin regulates acute chill coma recovery in Drosophila melanogaster. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2021; 133:103548. [PMID: 33549817 PMCID: PMC8180487 DOI: 10.1016/j.ibmb.2021.103548] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 01/09/2021] [Accepted: 01/31/2021] [Indexed: 05/10/2023]
Abstract
When chill-susceptible insects are exposed to low temperatures they enter a temporary state of paralysis referred to as a chill coma. The most well-studied physiological mechanism of chill coma onset and recovery involves regulation of ion homeostasis. Previous studies show that changes in metabolism may also underlie the ability to recovery quickly, but the roles of genes that regulate metabolic homeostasis in chill coma recovery time (CCRT) are not well understood. Here, we investigate the roles of Sestrin and Spargel (Drosophila homolog of PGC-1α), which are involved in metabolic homeostasis and substrate oxidation, on CCRT in Drosophila melanogaster. We find that sestrin and spargel mutants have impaired CCRT. sestrin is required in the muscle and nervous system tissue for normal CCRT and spargel is required in muscle and adipose. On the basis that exercise induces sestrin and spargel, we also test the interaction of cold and exercise. We find that pre-treatment with one of these stressors does not consistently confer acute protection against the other. We conclude that Sestrin and Spargel are important in the chill coma response, independent of their role in exercise.
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Affiliation(s)
- Tyler Cobb
- Wayne State University School of Medicine, Department of Physiology, Detroit, MI, 48201, USA
| | - Deena Damschroder
- Wayne State University School of Medicine, Department of Physiology, Detroit, MI, 48201, USA
| | - Robert Wessells
- Wayne State University School of Medicine, Department of Physiology, Detroit, MI, 48201, USA.
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15
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Cobb T, Sujkowski A, Morton C, Ramesh D, Wessells R. Variation in mobility and exercise adaptations between Drosophila species. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2020; 206:611-621. [PMID: 32335730 PMCID: PMC7314734 DOI: 10.1007/s00359-020-01421-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 04/08/2020] [Accepted: 04/15/2020] [Indexed: 12/30/2022]
Abstract
Locomotion and mobility have been studied extensively in Drosophila melanogaster but less is known about the locomotor capacity of other Drosophila species, while the response to chronic exercise in other species has yet to be examined. We have shown that adult male D. melanogaster adapt to exercise training with improved running endurance, climbing speed, and flight ability compared to unexercised flies. Here, we examine baseline mobility of D. sechellia, D. simulans, and D. virilis, and their response to chronic exercise training. We found significant interspecific differences in mobility and in the response to exercise. Although there is a significant sex difference in exercise adaptations in D. melanogaster, intraspecific analysis reveals few sex differences in other Drosophila species. As octopamine has been shown to be important for exercise adaptations in D. melanogaster, we also asked if any observed differences could be attributed to baseline octopamine levels. We find that octopamine and tyramine levels have the same rank order as baseline climbing speed and endurance in males, but do not predict the response to chronic exercise in males or females. Future research should focus on determining the mechanisms responsible for the inter- and intraspecific differences in mobility and the response to exercise.
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Affiliation(s)
- Tyler Cobb
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Alyson Sujkowski
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Courtney Morton
- Department of Kinesiology, Wayne State University, Detroit, MI, 48201, USA
| | - Divya Ramesh
- Department of Biology, University of Konstanz, 78464, Konstanz, Baden Württemberg, Germany
| | - Robert Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
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16
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Cao T, Sujkowski A, Cobb T, Wessells RJ, Jin JP. The glutamic acid-rich-long C-terminal extension of troponin T has a critical role in insect muscle functions. J Biol Chem 2020; 295:3794-3807. [PMID: 32024695 PMCID: PMC7086023 DOI: 10.1074/jbc.ra119.012014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/03/2020] [Indexed: 12/12/2022] Open
Abstract
The troponin complex regulates the Ca2+ activation of myofilaments during striated muscle contraction and relaxation. Troponin genes emerged 500-700 million years ago during early animal evolution. Troponin T (TnT) is the thin-filament-anchoring subunit of troponin. Vertebrate and invertebrate TnTs have conserved core structures, reflecting conserved functions in regulating muscle contraction, and they also contain significantly diverged structures, reflecting muscle type- and species-specific adaptations. TnT in insects contains a highly-diverged structure consisting of a long glutamic acid-rich C-terminal extension of ∼70 residues with unknown function. We found here that C-terminally truncated Drosophila TnT (TpnT-CD70) retains binding of tropomyosin, troponin I, and troponin C, indicating a preserved core structure of TnT. However, the mutant TpnTCD70 gene residing on the X chromosome resulted in lethality in male flies. We demonstrate that this X-linked mutation produces dominant-negative phenotypes, including decreased flying and climbing abilities, in heterozygous female flies. Immunoblot quantification with a TpnT-specific mAb indicated expression of TpnT-CD70 in vivo and normal stoichiometry of total TnT in myofilaments of heterozygous female flies. Light and EM examinations revealed primarily normal sarcomere structures in female heterozygous animals, whereas Z-band streaming could be observed in the jump muscle of these flies. Although TpnT-CD70-expressing flies exhibited lower resistance to cardiac stress, their hearts were significantly more tolerant to Ca2+ overloading induced by high-frequency electrical pacing. Our findings suggest that the Glu-rich long C-terminal extension of insect TnT functions as a myofilament Ca2+ buffer/reservoir and is potentially critical to the high-frequency asynchronous contraction of flight muscles.
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Affiliation(s)
- Tianxin Cao
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Alyson Sujkowski
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Tyler Cobb
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Robert J Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Jian-Ping Jin
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan 48201
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17
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Damschroder D, Richardson K, Cobb T, Wessells R. The effects of genetic background on exercise performance in Drosophila. Fly (Austin) 2020; 14:80-92. [PMID: 33100141 PMCID: PMC7714460 DOI: 10.1080/19336934.2020.1835329] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/29/2020] [Accepted: 10/06/2020] [Indexed: 10/29/2022] Open
Abstract
The use of the Drosophila model for studying the broad beneficial effects of exercise training has grown over the past decade. As work using Drosophila as an exercise model becomes more widespread, the influence of genetic background on performance should be examined in order to better understand its influence on assessments used to quantitatively measure and compare exercise phenotypes. In this article, we review the various methods of exercise training Drosophila, and the performance of different wild-type Drosophila strains on various physiological assessments of exercise response. We conclude by summarizing the performance trends of commonly used strains.
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Affiliation(s)
- Deena Damschroder
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Kristin Richardson
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Tyler Cobb
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Robert Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, USA
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18
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Kim M, Sujkowski A, Namkoong S, Gu B, Cobb T, Kim B, Kowalsky AH, Cho CS, Semple I, Ro SH, Davis C, Brooks SV, Karin M, Wessells RJ, Lee JH. Sestrins are evolutionarily conserved mediators of exercise benefits. Nat Commun 2020; 11:190. [PMID: 31929512 PMCID: PMC6955242 DOI: 10.1038/s41467-019-13442-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 11/06/2019] [Indexed: 01/04/2023] Open
Abstract
Exercise is among the most effective interventions for age-associated mobility decline and metabolic dysregulation. Although long-term endurance exercise promotes insulin sensitivity and expands respiratory capacity, genetic components and pathways mediating the metabolic benefits of exercise have remained elusive. Here, we show that Sestrins, a family of evolutionarily conserved exercise-inducible proteins, are critical mediators of exercise benefits. In both fly and mouse models, genetic ablation of Sestrins prevents organisms from acquiring metabolic benefits of exercise and improving their endurance through training. Conversely, Sestrin upregulation mimics both molecular and physiological effects of exercise, suggesting that it could be a major effector of exercise metabolism. Among the various targets modulated by Sestrin in response to exercise, AKT and PGC1α are critical for the Sestrin effects in extending endurance. These results indicate that Sestrin is a key integrating factor that drives the benefits of chronic exercise to metabolism and physical endurance.
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Affiliation(s)
- Myungjin Kim
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Alyson Sujkowski
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Sim Namkoong
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea
| | - Bondong Gu
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Tyler Cobb
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Boyoung Kim
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Allison H Kowalsky
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Chun-Seok Cho
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Ian Semple
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Seung-Hyun Ro
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
- Department of Biochemistry, University of Nebraska, Lincoln, NE, 68588, USA
| | - Carol Davis
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Susan V Brooks
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Michael Karin
- Department of Pharmacology, University of California San Diego, La Jolla, CA, 92093, USA
| | - Robert J Wessells
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, 48201, USA.
| | - Jun Hee Lee
- Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, 48109, USA.
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19
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Sujkowski A, Spierer AN, Rajagopalan T, Bazzell B, Safdar M, Imsirovic D, Arking R, Rand DM, Wessells R. Mito-nuclear interactions modify Drosophila exercise performance. Mitochondrion 2019; 47:188-205. [PMID: 30408593 PMCID: PMC7035791 DOI: 10.1016/j.mito.2018.11.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 10/19/2018] [Accepted: 11/03/2018] [Indexed: 02/08/2023]
Abstract
Endurance exercise has received increasing attention as a broadly preventative measure against age-related disease and dysfunction. Improvement of mitochondrial quality by enhancement of mitochondrial turnover is thought to be among the important molecular mechanisms underpinning the benefits of exercise. Interactions between the mitochondrial and nuclear genomes are important components of the genetic basis for variation in longevity, fitness and the incidence of disease. Here, we examine the effects of replacing the mitochondrial genome (mtDNA) of several Drosophila strains with mtDNA from other strains, or from closely related species, on exercise performance. We find that mitochondria from flies selected for longevity increase the performance of flies from a parental strain. We also find evidence that mitochondria from other strains or species alter exercise performance, with examples of both beneficial and deleterious effects. These findings suggest that both the mitochondrial and nuclear genomes, as well as interactions between the two, contribute significantly to exercise capacity.
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Affiliation(s)
- Alyson Sujkowski
- Department of Physiology, Wayne State University, Detroit, MI, United States
| | - Adam N Spierer
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI, United States
| | - Thiviya Rajagopalan
- Department of Physiology, Wayne State University, Detroit, MI, United States
| | - Brian Bazzell
- Department of Physiology, Wayne State University, Detroit, MI, United States
| | - Maryam Safdar
- Department of Physiology, Wayne State University, Detroit, MI, United States
| | - Dinko Imsirovic
- Department of Physiology, Wayne State University, Detroit, MI, United States
| | - Robert Arking
- Department of Biological Sciences, Wayne State University, Detroit, MI, United States
| | - David M Rand
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI, United States
| | - Robert Wessells
- Department of Physiology, Wayne State University, Detroit, MI, United States.
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